Changeable gearing for bicycles.



No. 645,446. Patented Mar. l3, I900.

G. S. ADAMS.

CHANGEABLE GEARING FOR BICYCLES.

' {Application filed Oct. 14, 1899.}

(No Model.)

lwwwboz 62x). Gzdeon flAcZamS dummy UNITED Sat/wins P TENT GIDEON S. ADAMS, OF CAMDEN, NEW JERSEY, ASSIGNOR OF ONE-THIRD TO W. W. ARMSTRONG, OF SAME PLAOEL CHANGEABLE GEARINGFOR BlCYCLESi SPEGIFIOA'I'IONforming part of Letters Patent No. 645,446, dated March 13, 1900. Application filed October 14; 1899. Serial No. 733,638. (No model-) T0 at whom it may concern.-

Be it known that I, GIDEON S. ADAMS, a citizen of the United States, residing at Camden, in the county of Camden and State of New Jersey, have invented a new and useful Changeable Gearing for Bicycles, of which the following is a specification.

This invention relates to a driving-gear for bicycles or similar vehicles; and it has for one object to provide a new and useful construotion of changeable gearing which maybeconveniently adjusted by the rider to provide means for increasing or diminishing the speed, as well as changing the leverage or power to facilitate hill-climbing or riding against the wind.

A further objectof the invention is to provide a novel form of gearing the parts of which are so constructed and arranged as to permit of the same being readily assembled in connection with the crank-hanger and axle of the machine, while at the same time being be thrown out of action to permit of the rider coasting.

With these and many other objects in view, which will more readily appear as the nature of the invention is better understood, the same consists in the novel construction, combination, and arrangement of parts hereinafter more fully described, .illustrated,and claimed.

The essential features of the present invention are necessarily susceptible to some modification without departing from the spirit or scope thereof; but the preferred embodiment of the improved gearing is illustrated in the accompanying drawings, in which- Figure 1 is a perspective view of the rear portion of a bicycle equipped with a changeable gear constructed in accordance with the present invention. Fig. 2 is an enlarged longitudinal sectional view through the crankhanger of the frame, showing one of the sprocket-wheels clutched for use and the other unclutched and free to loosely rotate without affecting the machine. Fig. 3 is a vertical sectional view on the line 3 3 of Fig. 2, the view also including sufficient of the frame to show the mounting of the shifting rod and the locking-latch therefor. Fig. 4 is a detail in perspective of one of the sprocket-wheels, showing attached to the inner side thereof the retaining-ring therefor. Fig. 5 is a detail in perspective of one of the end bearing-bushings forming a part of the attachment. Fig. 6 is a detail in perspective of a portion of one of the crank-arms.

' Similar numerals of reference designate corresponding parts in the several figures of the drawings.

In carrying out the'present invention the parts constituting the changeable gearing can be utilized in connection with any of the ordinary types of safety-bicycles, and for illustrative purposes there is shown in the drawings an, ordinary frame 1 of a bicycle be longing to this class. The said bicycle-frame is constructed of the usual members and is provided at the juncture of the rear-fork bars and the lower inclined reach-bar with the ordinary tubular crank-hanger 2. In applying the invention to the machine the tubular crank-hanger 2 is provided at its opposite open ends with interiorly-threaded portions 3, which detachably receive the exteriorlythreaded hubs 4, projected from one side of the end bushings 5 for the crank-hanger. When the end bushings 5 are fitted in place, with their threaded hubs 4 engaged within the threaded ends of the crank-hanger, the said bushings serve to close the open ends of the crank-hanger to keep out dust from the interior thereof; but the main purpose of the end bushings in the present invention is to provide bearing-supports for the revoluble different-sized sprocket-wheels, to be pres ently referred to. To provide for the proper journaling of the different-sized sprocketwheels, each of the end bushings 5 is provided with an annular bearing-collar 6 and upon the outer side thereof, next to the crank-axle 7, with a ball-race 8, adapted to lie opposite and register with a smaller race 9, formed in the inner side of the sprocket-wheel 10, and these ball-races are designed to accommodate therein a series of antifriction bearing-balls 11, which provide a ball-bearing between the adjacent contacting faces of the end bushing 5 and the sprocket-Wheel 10 at one side thereof.

To provide for the journal-support of the sprocket-wheel 10 directly upon the end of the crank-hanger contiguous thereto, the said sprocket-Wheel has bolt-ed or otherwise detachably fastened to the inner side thereof a retaining-ring 11. The retaining-ring 11 is readily detachable from the sprocket-Wheel 10 to facilitate the assembling of the parts upon the machine, and said retaining-ring is provided with an integral laterally-offset bent or angled bearing-flange 12, adapted to loosely embrace the annular bearing-collar 6 of' the end bushing 5, which bearing-collar projects beyond the periphery of the crank-hanger to provide a bearing-support for the sprocketwheel. By reason of the construction described it will be seen that the sprocket-wheel may be properly said to be journaled directly upon the end of the crank-hanger, while at the same time the parts are so mounted as to permit of conveniently separating whenever necessary.

A description has only been given of the construction and arrangement of parts at one end of the crankhanger, inasmuch as the parts are duplicated at both ends; but at this point it may be observed that the sprocketwheels 10 at opposite ends of the crank-hanger are respectively of diiferent sizes and adapted to receive thereover the chains 13, which lead to the complementary sprocket-wheels on the rear driving-axle of the machine, which arrangement of chains is familiar to those skilled in the art and for which no claim is made in the present application.

Each of the sprocket-wheels 10 has projected centrally from the outer side thereof a toothed clutch-collar 14, which cooperates with a similarly-toothed clutch member 15, carried at the inner side of the collar 16 of the crank-arm 17, which is fitted on the end of the crank-axle by any approved means. The crank-axle 7 is fitted at both ends with crankarm's carrying at their inner sides the toothed clutch members 15, and said axle is of a sufficient length to permit of a longitudinal movement thereof in the end bushings to provide for carrying the toothed clutch members 15 into interlocking engagement with the complementary clutch members 14c carried by the sprocket-wheels 10. To provide for the longitudinal shifting movement of the crankaXle 7, the same is .provided intermediate its ends within the crank-hanger with an annularly-grooved collar 18, which loosely receives therein a roller 19, mounted on one end of the crank-arm 20, projecting through an opening 21 in the crank-hanger and formed at the lower end of a shifting rod 22. The shifting rod 22 is mounted in suitable bearings provided on the machine-frame and has pivotally attached to its upper end one end of a latch-bar 23, which is arranged contiguous to the seat-post beneath the seat and is adapted to engage with any of a series of the notches 24 in the notched segement or bar 25, which may be conveniently fastened to the rear braces of the frame near the upper end of such braces. v

The latch-bar 23 maybe locked in either of the three positions-namely, to hold the axle clutched to either of the sprocket-wheels or unclutched from both when the rider desires to coast-it being observed that when the shifting rod 22 is turned on its axis in one direction the crank-axle 7 will be moved longitudinally, so as to carry the toothed clutch member 15 at one end thereof into engagement with the complementary member 140E the adjacent sprocket-wheel, at the same time unclutching the opposite wheel. A reverse movement of'the shifting rod will'secure an opposite action by throwing the other sprocket wheel in use. In this way the rider has the gearing completely under control and may change the gear from high to low, or vice versa, at will.

In order to secure a maximum efficiency for the changeable gearing, the clutch members or collars 14 on the sprocket-wheels are preferably fitted with dust-bands 26, projecting beyond the same and adapted to receive therein the clutch members 15, carried by the crank-arm, as plainly shown in Fig. 2 of the drawings.

From the foregoing it is thought that the operation and many advantages of the herein-described invention will be apparent to those skilled in the art without further description, and it will be understood that various changes in the size, shape,- proportion, and minor details of construction may be resorted to without departing from the spirit or sacrificing any of the advantages of the in vention. v

Having thus descrihedthe invention, what is claimed as new, and desired to be secured by Letters Patent, is-

1. In a changeabfe gear for bicycles, the combination with a crank-hanger, of bush ings secured in and closing the ends of said crank-hanger and provided with protruding flanges and with ball-races in the outer end faces thereof, different-sized sprocket-wheels revolubly mounted on the flanged bushings 15 wheels and engaging circumferentially and laterally with the flanges of the bushings to connect the sprocket-wheels directly and revolubly thereto, pedal-cranks fast with the axle, clutch members on the opposing faces of the pedal-cranks and the sprocket-wheels,

and means for shifting the axle endwise, substantially as described. 7

In testimony that I claim the foregoing as my own I have hereto affixed my signature in the presence of two Witnesses.

G. S. ADAMS.

Witnesses:

JOHN H. SIGGERS, D. P. WoLHAUPrnR. 

